1 files changed, 38 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 5a48df235a9..d86534d5f8d 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -3491,6 +3491,13 @@ Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
     }
   }
 
+  // Find out if any arguments are required to be integer constant
+  // expressions.
+  unsigned ICEArguments = 0;
+  ASTContext::GetBuiltinTypeError Error;
+  getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
+  assert(Error == ASTContext::GE_None && "Should not codegen an error");
+
   SmallVector<Value*, 4> Ops;
   llvm::Value *Align = nullptr;
   for (unsigned i = 0, e = E->getNumArgs() - 1; i != e; i++) {
@@ -3553,7 +3560,17 @@ Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
         continue;
       }
     }
-    Ops.push_back(EmitScalarExpr(E->getArg(i)));
+
+    if ((ICEArguments & (1 << i)) == 0) {
+      Ops.push_back(EmitScalarExpr(E->getArg(i)));
+    } else {
+      // If this is required to be a constant, constant fold it so that we know
+      // that the generated intrinsic gets a ConstantInt.
+      llvm::APSInt Result;
+      bool IsConst = E->getArg(i)->isIntegerConstantExpr(Result, getContext());
+      assert(IsConst && "Constant arg isn't actually constant?"); (void)IsConst;
+      Ops.push_back(llvm::ConstantInt::get(getLLVMContext(), Result));
+    }
   }
 
   switch (BuiltinID) {
@@ -4222,9 +4239,27 @@ Value *CodeGenFunction::EmitAArch64BuiltinExpr(unsigned BuiltinID,
     return Builder.CreateCall(F, {Arg0, Arg1});
   }
 
+  // Find out if any arguments are required to be integer constant
+  // expressions.
+  unsigned ICEArguments = 0;
+  ASTContext::GetBuiltinTypeError Error;
+  getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
+  assert(Error == ASTContext::GE_None && "Should not codegen an error");
+
   llvm::SmallVector<Value*, 4> Ops;
-  for (unsigned i = 0, e = E->getNumArgs() - 1; i != e; i++)
-    Ops.push_back(EmitScalarExpr(E->getArg(i)));
+  for (unsigned i = 0, e = E->getNumArgs() - 1; i != e; i++) {
+    if ((ICEArguments & (1 << i)) == 0) {
+      Ops.push_back(EmitScalarExpr(E->getArg(i)));
+    } else {
+      // If this is required to be a constant, constant fold it so that we know
+      // that the generated intrinsic gets a ConstantInt.
+      llvm::APSInt Result;
+      bool IsConst = E->getArg(i)->isIntegerConstantExpr(Result, getContext());
+      assert(IsConst && "Constant arg isn't actually constant?");
+      (void)IsConst;
+      Ops.push_back(llvm::ConstantInt::get(getLLVMContext(), Result));
+    }
+  }
 
   auto SISDMap = makeArrayRef(AArch64SISDIntrinsicMap);
   const NeonIntrinsicInfo *Builtin = findNeonIntrinsicInMap(